1. Field of the Invention
The present disclosure relates to an optical recording medium, erasure apparatus and erasure method thereof.
2. Description of the Related Art
Conventionally, optical recording media (optical disks) such as CD, DVD and BD are used as media for recording and reading data such as document, music and video. Optical recording media can record data by, for example, transforming an organic pigment recording layer included in the optical recording media using a laser beam for writing and read data by irradiating the organic pigment recording layer with a laser beam for reading from differences in intensity of the reflected light.
Such optical recording media have a feature of being able to repeatedly read recorded data for a long period of time, and are therefore widely used to record personal data, corporate data or the like. Furthermore, rental services are also widely available whereby contents such as music data or video data are recorded in optical recording media and the optical recording media are lent out to users.
When optical recording media that record personal data or corporate data are disposed of, data is generally erased before the disposal to prevent leakage of the recorded data. Conventionally, a method of overwriting data recorded in optical recording media with meaningless data using a data writing apparatus is adopted to erase the data (e.g., see Japanese Patent Laid-Open No. 2002-304736), but overwriting recorded data one by one is troublesome and time-consuming work and forces users to bear the burden.
On the other hand, a rental service assumes that optical recording media which have been lent out are collected back, but a procedure for sending back or returning the media constitutes a burden to users and management of the recording media which have been lent out and a procedure for collecting back the media constitutes a burden to rental service providers.
Thus, it is desirable to reduce the burden in erasing data in optical recording media. In a rental service of optical recording media in which contents are recorded, it is also desirable to reduce the burden on users and rental service providers to collect back the optical recording media.